1-Naphthalenesulfonic acid, 6-diazo-5,6-dihydro-5-oxo-, thiodi-1,2-naphthalenediyl ester 2,2'-Dihydroxy-1,1'-dinaphthylsulfide, bis(2-diazo-1-naphthol-5-sulfonate) 68901-25-7 EINECS 272-668-3 Thiodinaphthalene-1,2-diyl tetrakis(6-diazo-5,6-dihydro-5-oxonaphthalene-1-sulphonate)